package com.collection.hashmaps;

import java.util.HashMap;

public class JavaHashMapExample {
	 public static void main(String[] args) {
		   
		    //create object of HashMap
		    HashMap hMap = new HashMap();
		   
		    /*
		      Add key value pair to HashMap using
		      Object put(Object key, Object value) method of Java HashMap class,
		      where key and value both are objects
		      put method returns Object which is either the value previously tied
		      to the key or null if no value mapped to the key.
		    */
		   
		    hMap.put("One", new Integer(1));
		    hMap.put("Two", new Integer(2));
		   
		    /*
		      Please note that put method accepts Objects. Java Primitive values CAN NOT
		      be added directly to HashMap. It must be converted to corrosponding
		      wrapper class first.
		    */
		   
		    //retrieve value using Object get(Object key) method of Java HashMap class
		    Object obj = hMap.get("One");
		    System.out.println(obj);  
		   
		    /*
		      Please note that the return type of get method is an Object. The value must
		      be casted to the original class.
		    */
		 
		   
		  }
}
